The present disclosure relates generally to convergence measurement in a computer network, and more specifically, a distributed system for IGP convergence measurement.
OSPF (Open Shortest Path First) and IS-IS (Intermediate System to Intermediate System) are link state Interior Gateway Protocols (IGPs) used in today's IP (Internet Protocol) networks. Following the widespread deployment of real time applications such as VoIP (Voice over IP) and VPNs (Virtual Private Networks), much tighter Service Level Agreements (SLAs) are required, leading to faster IGP convergence requirements. The faster IGP convergence requirements have resulted in a need for systems to monitor and assess IGP convergence performance.
Difficulties in monitoring IGP convergence are due to the size of a network (e.g., large network may include around 950 nodes and 500 edge routers), the smallness of the measured parameter (convergence typically occurs in a few hundreds of milliseconds), the non-predictability of convergence events (topological failures may occur at any time and location), and the level of details required to correctly assess convergence performance.